package STUDENT.TRANDAODAIVI.QUESTION;


public interface QuackBehavior {
	void quack();
}

class Quack implements QuackBehavior{
	public void quack(){
		System.out.println("Quack");
	}
}

class Squeak implements QuackBehavior{
	public void quack(){
		System.out.println("Squeak");
	}
}

class MuteQuack implements QuackBehavior{
	public void quack(){
		System.out.println("No-sound");
	}
}